The Obama administration unveiled the most authoritative report to date on the effects of global warming in America today in an effort to persuade the public of the need to act now to prevent the sweeping and life-altering consequences of global warming.

Americans have been living with the heavy downpours, rising sea levels, and blistering summer heat waves produced by man-made climate change for 30 years said the report, which was produced by more than 30 scientists working across 13 government agencies.

The effects of climate change will be even more severe by the end of the century.

"The projected rapid rate and large amount of climate change over this century will challenge the ability of society and natural systems to adapt," the report said.

Today's release of the study, titled Global Climate Change Impacts in the United States, was overseen by a San Francisco-based media consulting company, and was part of a carefully crafted strategy by the White House to help build public support for a climate change bill that has run into opposition from some Democrats as well as Republicans in Congress.

The nearly 200-page study was scrubbed of the usual scientific jargon, and was given a high-profile release by Obama's science advisor, John Holdren, and the head of the National Oceanic and Atmospheric Administration (NOAA), Jane Lubchenco.

"I really believe this report is a game changer. I think that much of the foot-dragging in addressing climate change is a reflection of the perception that climate change is way down the road in the future and it affects only remote parts of the world," she told a press conference today. "This report says climate change is happening now. It is happening in our own back yard."

Average temperatures in the US have risen by 1.5F (0.8C) over the last 50 years, the report said. Rainfall in major storms has increased 20% over the last 100 years - with the heaviest downpours in the north-east. Sea levels have risen up to eight inches along some parts of the east coast.

The consequences of those changes are rippling through every region of the US between Alaska and Hawaii - from the disruption of salmon stocks and shift in butterfly migrations to rising incidence of asthma and now well-documented signs like increasingly deadly hurricanes and melting icecaps in the Arctic.

If today's generation fails to act to reduce the carbon emissions that cause global warming, climate models suggest temperatures could rise as much as 11F by the end of the century.

That translates into catastrophic consequences for human health and the economy such as more ferocious hurricanes in coastal regions - in the Pacific as well as the Atlantic, punishing droughts to the south-west, and increasingly severe winter storms in the north-east and around the Great Lakes.

The majority of North Carolina's beaches would be swallowed up by the sea. New England's long and snowy winters might be cut short to as little as two weeks. Summers in Chicago could be a time of repeated deadly heat waves. Los Angelenos and residents of other big cities will be choking because of deteriorating air quality.

Future generations could face potential food shortages because of declining wheat and corn yields in the breadbasket of the mid-west, increased outbreaks of food poisoning and the spread of epidemic diseases.

The physical infrastructure could also be threatened with storm surges and sea level rises engulfing 2,400 miles of road and other key infrastructure on the Gulf coast. Airports built on permafrost in Alaska will need to be relocated, the electrical grid will strain to meet the increased demand for air conditioning in summer, and ageing sewer systems will be brought to bursting point by heavy run-off in 770 American cities and towns.

"The most important thing in this report is that the impacts of climate change are not something your children might theoretically see 50 years from now," said Tony Janetos, one of the study's authors and a director of the Joint Global Change Research Institute at the University of Maryland.

"The thing that concerns me the most is that we have a whole host of impacts that we now observe in the natural world that are occurring sooner and more rapidly and that appear to be larger than we might have expected 10 years ago. If anything we might have underestimated the rate and the impact of changes in the climate system."

The study initially got under way when George Bush was president as part of a regular exercise mandated by Congress. It was finalised in late April, but Obama administration officials spent several weeks planning today's release, honing the language and graphics to make it accessible to non-scientists and to sharpen its core message: America must take action on climate change.

As part of the PR surrounding the release of the report, the administration approached the San Francisco consulting firm, Resource Media, which specialises in environmental campaigning, to produce a shorter and more digestible brochure of today's report for wider public distribution.

On the morning of 16 April, at a meeting in Washington, more than 30 NOAA scientists, climate change experts from a number of universities, environmental activists and media strategists discussed how to engage various communities with the findings of the report - town mayors, religious groups, even kindergarten pupils.

"The implied message here is that we can either pay in a more controlled way to bring about changes in our energy system which we can do in a way which will [have] benefits for jobs ... or we can do nothing now but we are still going to have to pay in the longer term and the damages are far less controllable," said Richard Moss, a former director of the US climate change science programme and vice-president for the World Wildlife Fund.

The release appeared timed to help Democratic leaders in Congress meet an ambitious target of passing a climate change bill through the House of Representatives by 26 June. The Democratic speaker, Nancy Pelosi, wants to hold a vote before the House breaks up for the 4 July Independence Day holiday.

But the bill has been opposed by some Democratic members of Congress, especially those from agricultural states who say that putting limits on greenhouse gas emissions will hurt farmers' economic interests.

• This article was amended on Wednesday 17 June 2009. We confused the absolute with the incremental in reporting that a rise in temperature of 1.5F corresponds to an decrease of 17C. It is a rise of 0.8C. This has been corrected.